Spraying and smoke-laying apparatus

ABSTRACT

An apparatus for injecting a flowable medium such as a liquid while simultaneously breaking up or vaporizing the medium in which a pulsating burner is provided with a resonating tube with the medium being supplied to the burner resonating tube for being conveyed outwardly by the discharge from the burner resonating tube. An air resonating tube coaxially surrounds the burner resonating tube for the flow of air therethrough in the same direction as the products of combustion from the burner passed through the burner resonating tube and the tubes are tuned to a frequency of about 50 to 160 Hertz and are so tuned relative to each other that the frequencies therein are about one-half cycle apart.

United States Patent 11 1 Locher et a1.

[ 51- 'De c. 1 7, 1974 SPRAYING AND SMOKE-LAYING APPARATUS inventors:Otto Locher; Franz Haag; Paul Bongartz, all of Isny, Germany [73] HeimoGeraetebau Gesellschaft mit beschrankter 'Haftung, lsny, Germany Filed:Apr. 25, 1972 App]. No.: 247,296

Assignee:

[30] Foreign Application Priority Data Apr. 28, 1971 Germany 2120749 us.Cl. 252/359 co, 60/39.77 rm. Cl. .3010, BOlf, 1301 13/00 Field of Search252/359 co, 3055.43/129'; 47/2; 239/4, 102, 337,398; 60/39.77, 39.78,

References Cited UNITED STATES PATENTS Tenney et al. 60/3977 X Tenney eta1. 122/24 Campbell 60/3977 PERFORATED PLATE PULSATING BURNER COOLINGAIR/- 3/1956 Tenney et a]; 252/359 CG 2,857,332 10/1958 Tenney-et a1.252/359 CG 2,926,855 3/1960 Durret a1 252/359 CG 2,970,430 2/1961-Curtis et a1. 60/3977 X 3,093,962 6/1963 Gluhareff 60/3977 X 3,242,0983/1966v Andrews 252/359 CG Primary Exarriiner-Jack Sofer Attorney,Agent, or Firm-Walter Becker [5 7 ABSTRACT An apparatus for injecting -a'flowable medium such as a liquid while simultaneously breaking up orvaporiz-v ing themedium in which a pulsating burner, is provided with aresonating tube with the medium being supplied to the burner resonatingtube for being conyeyed outwardly by the discharge from the burnerresonating. tube. An air resonating tube coaxially surrounds the burnerresonating tube for the flow of air therethrough in the same directionas the-products of combustion from the burner passed through the burnerresonating tube and the tubesare tuned to a frequency of about 50 to 160Hertz and are so tuned relative to each other that the frequenciestherein are about one-half cycle apart.

16 Claims, 6 Drawing Figures I sa o ms MIXTURE PLATE VALVE CHAMBERF'PREssuRE near FUEL RESERVOIR ,MANUALLY OPERABLE AIR PUMP TANK"\ZIQSTANDPIPE PATENTEUUEC] 71974 mm 3. {If 5 FOR SPARK PLUG l SPRAYINGAND SMOKE-LAYING APPARATUS The present invention relates to a sprayingor smokelaying apparatus,oespecially a portable spraying apparatus witha container for a substance to be sprayed and with an oscillating fireor pulsating burner (Schwingfeuer-Brenner), which operates withpulsating combustion and is fed with liquid fuel from a reservoir, saidcontainer being connected to a discharge conduit, and said burner beingconnected to a burner resonator.

Devices of the above mentioned type are supposed to afford an effectiveemployment thereof in connection with an insecticidal, acaricidal, andfungicidal treatment of hothouse culture, trees and brushes, and inconnection with the elimination of flies and mosquitoes on beaches, atresort or camping places, and also in connection with the disinfectionof surface and .space areas, while such devices should have the abilitywith a low fuel consumption to dispense large quantities of therespective substance. In this connection, the staying time of therespective substance within the region of the burner exhaust gases mustbe short in order to prevent the substances from thermallydisintegrating. Furthermore, devices of the above mentioned type shouldbe such that they can easily be handled, have a low weight, are simplein construction, and are generally not subject to disorders while beingable when incorrectly treated to shut themselves off automatically.

These and other objects and advantages of the present invention willappear more clearly from the following specification, in connection withthe accoinpanyin FIG. 2 illustrates the apparatus of FIG. I as seen fromthe side.

FIG. 3 is a top view of the arrangement of FIG. 2.

' metal member twisted around the axis-16 of the mixing neck over anangle of 180. Transverse to the axis 16 FIG. 4 shows a section takenalong the line.lV lV of FIG. 2 through the carburetor and the burnerunit of the apparatus.

FIG. 5 illustates a section taken along the line V-V of FIG. 3 throughthe fuel meteringdevice, said section through the carburetor and burnerunit. v

FIG. 6 represents a verticallongitudinal section taken along the lineVI-'VI of FIG. 3 through the valve 7 system of the apparatus accordingto the invention.

The spraying or smoke-laying apparatus according to the invention ischaracterized primarily in that the burner is connected to a mechanicalair intake valve and that the burner resonator is annularly surroundedby an at least approximately coaxial cool air resonator which at itsinlet is provided with a valve, preferably an aerodynamic valve.

According to further development of the invention, it is provided thatthe burner resonator and the cool air resonator are tuned upon eachother and coordinated to each other in such a way that at asubstantially equal fundamental frequency, the oscillation or pulsationin the burner resonator has over the cool air resonator a phasedisplacement by one-half cycle. Advantageously,

the axial length of the resonators amounts to at least approximatelyone-fourth of the wave length. In this way a particularly high airdelivery and a considerable kinetic energy is obtained with low outputlosses. Therefore. it is possible with low fuel consumption to dischargelarge quantities of the respectivesubstances to be sprayed bytheapparatus and to lay the smoke in a very fineatomi zed'form.

Referring now to the drawings in detail, the spraying and smoke-layingapparatus, according to the diagrammatic illustration of FIG. 1comprises a pulsating fire burner l with a burner resonator 2 formed bya cylindrical pipe and connected to said burner 1, and with an airresonator 3 coaxially arranged with said resonator -2, said resonator 3surrounding the burner and the res- The carburetor will be described ingreater detail. in

connection with FIGS. 4 and 5. The carburetor according to the buildingprinciple illustrated in FIG. 1 .is provided with an air intake funnel10 having an inserted valve plate 11, a central chamber 12 and aturbulence chamber 13 communicating with valve chamber' 12 through thebore of nozzle 9. The carburetor furthermore comprises a mixingneck 14connected to the valve chamber 12, into which mixing neck 14 there isinserted a twist body 15 which comprises a twist sheet in F-IG. 4 at theend of the body 15 there is provided a diaphragm plate or baffle plate17 which with regard to the wall of the suction pipe 20 leaves free anarrow annular gapfThe fuel or mixture passing through said-annular gapcan be ignited bya spark plug 18 which is inserted into a threadedportion (FIG. 4) welded to the 'suction pipe "20.. The ignitionenergy isfurnished to a high voltage buzzer'igniton device which in FIG. 1 isillustrated only diagrammatically and which comprises a 6-volt battery21, an ignition switch 22 and a high voltage coil 24 equipped withself-breaker contacts 23,. 2

duit 32 which in the direct vicinity of the open end face of the burnerresonator 2 leads into the latter.

In order to be able within a time unit and with finest atomization todischarge large quantities of the substance to be sprayed, the presentinvention additionally provides that in addition to the mechanicaldamming upof the fuel gas column by means of the valve plate 11 of theair funnel 10 there is also provided an aerodynamic damming up of thecooling airresonator 3. This damming up or tamping can be taken asblocking or driving down" the course of a stream or flow.'The

. length of said cool air resonator is tuned or selected cool airresonator tube 3, be phase displaced by half'a cycle while the length ofthe gas or air column pulsating in these resonators amounts toapproximately onefourth of the wave length. It has been foundadvantageous for the burner to select a pulsating frequency ofapproximately 80 pulsations per second, in other words 80 Hertz.

The aerodynamic damming up with the illustrated embodiment of theinvention is realized by means of a perforated plate 34 which isarranged directly downstream of the central inlet opening 35 of the coolair tube 3 and is fixedly connected to the wall of this resonator tube 3at the outer marginal portion of said plate 34. The perforated plate 34simultaneously serves for connecting the cool air resonator tube 3 andto this end is connected to the imperforate end face wall 37 of theburner 1 by a central bolt 36. Along its marginal zone, the perforatedplate 34 has a plurality of stamped-out inlet openings 38 which have acollar-shaped extension 39 extending inwardly as will be more clearlyseen from the cutout shown on an enlarged scale. These inlet openings 38are in the illustrated embodiment of the invention designated as Bordamouths and bring about that in any inflow direction, the cooling airwill encounter only low resistance, whereas the flow resistance in theopposite direction will be considerably higher. In view of thisdamming-up arrangement, the burner resonator 2 and the cool airresonator tube 3 oscillate almost together at their fundamentalfrequencies so that only low energy losses can occur..The result is aconsid-' erably higher output of substances to be sprayed and a bettercooling of the burner l.

The high output of the burner is considerably aided by the design of thecarburetor (see FIG. 4) which comprises a one-piece housing of die-castmetal. The fuel nozzle 9 is in this instance located centrally withregard to the mixing neck 14 and is arranged between the mixing neck 14and the turbulence chamber 13. In

the turbulence chamber 13 there continuously prevails a certainoverpressure which prior to the start of the operation of the burner maybe provided in the manner customary for pulsating fire devices by meansofa manually operable air pump 40. In view of this overpressure, acontinuous flow in the direction indicated by the arrow S toward themixing neck 14 during the intake phase which in this way is considerablyimproved. The die-cast metal housing furthermore comprises a connectingpassage 42 which leads into the valve chamber 12 of FIG. 4 and isintended for a connecting line 43 in FIG. 1 leading to the unit 31 forthe substance to be sprayed. Within the course of this connecting line43, and more specifically at 44, there is provided a filter and a checkvalve 45 in FIG. which will prevent a substance to be sprayed frompassing from the unit 31 to the carburetor. This valve which permits theoccurring repulsion pressure to pass into the unit 31 and the emergencyshut-off device 50, to be described further below, is mounted in ahollow chamber 46 of a cover 47, as shown in FIG. 5, and through a bore48 communicates with a chamber 49 which receives the filtering substanceof filter 44 and acts as means to permit condensing and absorption inchamber .49. I

In order to be able in the reservoir'28 to produce a sufficient deliverypressure for the substance to be sprayed or laid as smoke, the tank orreservoir 28 communicates through a pressure line 51 and a valve 53within this line 51 and is adapted to communicate with a secondconnecting passage 52 which communicates with the valve chamber 12 ofthe carburetor 8. The

valve 53 in FIG. 1, opens each time when subsequently to an intake cyclea combustion occurs and then a repulsion pressure is created in thevalve chamber 12. In the connecting line 55 for the air pump there isfurthermore provided a third valve 56 which, however, in contrast to theabove described valves and 53 will close in response to an occurringrepulsion pressure and will be opened only when for purposes of startingthe burner, the air pump is actuated to carry out a pressure stroke.

For purposes of increasing the safety of operation and in order tofacilitate the handling of the apparatus, the fuel tank 4 is directlyconnected to the carburetor 8 and together with the latter forms astructural unit. In this connection, the fuel stand pipe 5 is presedinto a cylindrical extension 57 at the die-cast metal housing of thecarburetor, said extension 57 extending into the interior of the fuelreservoir. Moreover, a pressure pipe 58 is folded into the tank wall andleads to the turbulence chamber 13 of the carburetor in the manner showndiagrammatically in FIG. 1.

For purposes of simplifying the handling of the appav ratus and in orderto obtain a long life of use for the device according to the invention,it is suggested that the die-cast metal part-60 of the carburetorhousing receives the structural elements of the dosing device for thefuel as illustrated in FIG. 1 at the numeral 6. The

dosing device forms an easily exchangeable structural unit which isinserted into a bore 61 extending through the die-cast metal part 60.The said bore has its upper end section provided with a thread 62. In acoaxial arrangement, the dosing device comprises a filter 63 for theentering fuel, a nipple 64 fixedlyconnected to the filter which isscrewed into the lower section of a bushing 65 and which has its centralsection provided with a'thread 66 by means of'which it is turned intothe thread 62 of the part 60, and permits firmly to clamp in the cover47 while interposing a sealing ring 67 and a sealing plate 68 with itsflange 69.

Bushing 65 has a central longitudinal bore 71 which has its uppersection widened and provided with a thread 72. Turned into this thread72 is the thread 74 of a plug of a cock 75, the upper end of whichis-provided with a handle 77 adapted to be withdrawn. By means of thehandle 77, the plug can be turned out of the illustrated closingposition and into the opening position to such an extent that betweenthe end face 78 at the tapering inner end section of said-plug 75 andthe bottom of the bore 71 therewill'be obtained a passage ofsufficiently large cross section for the fuel to the transverse bore 79which leads to the central fuel nozzle 9, as shown in FIGS. 4 and 5.

A setting bolt 81 with its thread 62 is longitudinally adjustably guidedin a central longitudinal bore of the plug 75. Bolt 81 has its upper'endprovided with a screw slot 83 for receiving a non-illustrated screwdriver'and continues at its lower end section in the form of a settingneedle which determines the flowthroughcross section for the incomingfuel. After setting the needle 85, the setting bolt 81 is arrested inits set position, and the handle 77 may be placed upon the free end ofplug 75 so as to be prevented from-rotation. An abutment pin 84 which isaxially parallelly pressed into flange 69 serves for preventing the plug75 from being unduly turned out of the bushing 65.

In a manner similar to the above described carburetor, also thesubstance containing unit- 31 forms a structural unit.

As will be seen more clearly from FIG. 6, theunit 31 comprises the abovementioned emergency shut-off device and a valve 87. Both members aremounted on a common lower part 88 which forms a die-cast metal deviceand has its end face 90 which forms the dividing plane relative to theupper portion 81 provided in a simple manner with machined-in passages91 and 92 for the passage of material or substance to be sprayed or laidas smoke. The said substance is in contrast to the arrangement of FIG. Idelivered from the container or tank 28 through a line 93 to the valve87 rather than standpipe 29 of FIG. 1 and from there passes throughpassage 91 through the central bore 94 of aneasily exchangeable filterbody 95 through the central bore 94 passes through a bore 97 to thepassage 92 as long as v the emergency shut-off device 50 occupies itsillustrated operational position, and from there passes through a changenozzle 102 which for facilitating the screwing-in and out is providedwith a crossbar 103. For connecting the discharge line 32, not shown inFIG. 6, there is provided a section 104.

The emergency shut-off device 50 comprises a pressure chamber which issealed against the outer atmosphere by a diaphragm 112 and which throughthe pressure line 43, shown in FIG. 1, is adapted to communicate withthe valve chamber 12 of the carburetor 8 and has only a very narrowconnecting bore 115 toward the outside. The pressure which builds up inchamber 110 under the influence of the exhaust gases in burner l keepsthe valve shank 116 of the emergency shut-off device 50 in spacerelationship to the mouth of the transverse bore 97 until the burnerworks properly. If, however, a disorder should occur, the pressure inchamber 110 will quickly drop through the compensating bore 115. In suchan instance the pressure spring 117 which rests against the housingcover 114 is adapted to press the diaphragm 112 together with the valveshank 116 into the chamber 110 to such an extent that the valve shankcloses the transverse bore 97. In

orderto secure this locking position, there is provided an eccentricallyarranged annular spring 118 which in such an instance of disorderengages an annular grodve 119 on the valve shank 116 and secures. theturned-off position. From this locking position, the valve shank 116 canbe returned into operational position only by pulling on the handle 120mounted on the valve shank. For purposes of obtaining a very fastturning off in response to the disappearance of the working pressureinthe pressure chamber 110, it is expedient when on the back side of thediaphragm 112 which faces away from the pressure chamber 110 the outerair pressure act s fully and therefore sufficiently large openings 114are provided in the housing cover 114.

With the embodiment illustrated in the drawings, a

high voltage buzzing ignition device is provided for igniting the fuelair mixture, which high voltage buzzing ignition device may, however,also be replaced by other heretofore known ignition systems. In eachinstance, however, it is expedient so to arrange the ignition de vice,in the manner shown in FIG. 2, that the ignition device is surrounded bythe container or tank 28 and the gasoline tank 4 and in this way isprotected against mechanical' damage from the outside.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular showing in the drawings, but alsocomprises any modifications within the scope of the appended claims.

What is claimed is: s

1. In an apparatus for fuel consumption and ejecting a flowable medium,as for spraying or smoke laying: a container for said medium, apulsating burner having an intake end for admission of a combustiblemixture and a discharge end, and a burner resonator having one endconnected to the burner discharge end and the other end open to form adischarge orifice, conduit means leading from said medium container tosaid burner resonator to supply said medium thereto, an air resonatortube coaxial with and surrounding said burner and burner resonator andhaving an air inlet upstream of the intake end of said burner resonatorand open at the other end to form a discharge orifice adjacent thedischarge end of saidburner resonator, an air inlet connected to saidburner, valve forming means connected to the air inlet end of said airresonator tube, said burner including an end section forming a mixingpassageleading substantially at right angles into said one end of saidresonator, the length of said passage bearing a predetermined ratio tothe length of said air resonator tube, said conduit means leading fromsaid medium container to said burner resonator being connected to thelatter near the discharge end thereof, said burner including acarburetor having a turbulence chamber spaced from the end of saidmixing passage opposite the burner end of the passage, a fuel nozzlecoaxial with the mixing passage and interposed between the mixingpassage and turbulence chamber and spaced from the adjacent end of themixing passage, a helical strip in the end of said end section,-and abaffle plate at the downstream end of said strip defining an annularspace with said mixing passage, said air inlet communicating with thespace between said mixing passage and said nozzle, and ignition means onthe downstream side of said baffle plate for igniting the fuel-airmixture in said passage. v

2. An apparatus according to claim. 1 in which said valve forming meansat the air inlet end of said air resonator tube is located upstream fromsaid one end of I 7 said burner and comprises a plate havingperforations therein which taper inwardly toward said air resonatortube.

3. An apparatus according to claim 2 in which said resonator tubes aretuned relative to each other such that at a natural frequency on theorder of from about 60 to about Hertz the oscillations in said burnerresonator aredisplaced about a half cycle from the oscillations in saidair resonator tube.

4. An apparatus according to claim 1 which includes a shut-off devicewith valve and a filter in series in said conduit means leading fromsaid medium container to said burner resonator, a control valve inseries with said shut-off device with valve andfilter, a housing memberin which said valve and filter are mounted to form a means connectingsaid surface to the atmosphere, and

lock means for releasably holding said control valve in closed position.

5. An apparatus according to claim 1 which includes a fuel tank and afuel conduit leading therefrom to said nozzle, said carburetor and fueltank forming a unitary structure.

6. An apparatus according to claim 5 which includes a firstconduitleading from the space between the said nozzle and the said passage tosaid medium container to supply pressure thereto and having a checkvalve openi'ng toward the medium container, a control valve in saidconduit means leading from said medium container and spring-urged towardclosed position and having a movable surface within an expansiblepressure chamber responsive to fluid pressure to open the control valve,a. second conduit leading from said space to said expansible chamber andhaving a check valve opening toward said expansible chamber,communication means connecting to the atmosphere to permit said controlvalve to closeupon interruption ofthe supply of pressure from saidsecond conduit to said expansible chamber, and'fuel flow metering meansin said fuel conduit to control the flow of fuel from said tank to saidnozzle.

7. An apparatus according to claim 6 which includes a passage-formingmeans from the space at the downstream side of said nozzle to saidconduit means to assist in the flow of said medium to said burnerresonator.

8. An apparatus according to claim 6 which includes a passage-formingmeans from the space at the downstream side of said nozzle to said fueltank above the fuel therein. 7

9. An apparatus according to claim 6 in which said space at thedownstreamend of said nozzle is subjected to pressure when combustiontakes place at the downstream side of said disc andis subjected tosubatmospheric pressure between incidents of combustion, and said airinlet is disposed between the atmosphere and said space and is in theform of an opening toward said space.

10. An apparatus. according to claim 6 in which said fuel flow meteringmeanscomprises a housing part having a tubular channel connecting saidfuel conduit to said nozzle, a filter at the upstream end of saidchannel, a bushing in the channel at the downstream end of said filterhaving a central bore, a plug adjustable in said bushing for opening andclosing the downstream end of said bore, and a needle valve adjustablein said plug for adjustably controlling the flow of fuel through saidbore.

ll. An apparatus according to claim 10 in which saidfilter and bushingand plug and needle valve are in the form ofa unitary structureinsertable in and removable from said channel as a unit, said housingpart including a separable portion defining at least a part of saidsecond conduit and a part of said channel, said bushing having an endflange overlying said separable portion and being threaded into saidhousing part thereby to clamp said portion to said housing, said-portionhaving therein the said check valve in said second conduit and a filterelement serially connected to the check valve.

12. An apparatus according to claim 10 in which said plug is threadedinto said bushing and has one end protruding from the bushing. a handleremoveably mounted on the protruding end of said plug; and means saidhandle when turbulence chamber and including a check valve open ingtoward said turbulence chamber.

14 In an apparatus for fuel consumption and ejecting a flowable medium,as'for spraying or smoke laying: a

container for said medium, a pulsating burner having an intake end foradmission of a combustible mixture and a discharge end, and a burnerresonator having one end connected to the burner discharge end'and theother end open to form a discharge orifice, conduit means leading fromsaid medium container to said burner and burner resonator to supply saidmedium thereto, an air resonator tube coaxial with and surrounding saidburner resonator and having an air inlet upstream-of the intake end ofsaid burner resonator and open at the other end to form a dischargeorifice adjacent the discharge end of said burner resonator, an airinlet connected-to said burner, valve forming means connected to the airinlet end of said air resonator tube,

a shut off device with valve and a filter in series in said conduitmeans leading from said medium container to said burner'resonator, acontrol valve in series with said shut off device with valve and filter,a housing member in which said.valve and filter are mounted to form aunit, said control valve being spring biased toward check valve openingtoward the surface, communication means connecting said surface to theatmosphere,

and lock means forreleasably holding said control valve in closedposition, said' housing member being formed of two parts in face-to-facesealed engagement and defining therebetween the portions of said conduitmeans leading between said valve and filter.

15. In an apparatus for fuel consumption and ejecting a flowable medium,as for spraying or smoke laying: a container for said medium, apulsating burner having,

an intake end for admission of a combustible mixture and a dischargeend, and a burner resonator having one end connected to theburnerdischarge end and the other end open to form a discharge orifice,conduit means leading'from said medium container to said burnerresonator to supply said medium thereto, an air resonator tube coaxialwith and surrounding said burner and burnerresonator and having an airinlet upstream of the intake end of said burner resonator and open ,atthe other end to form a discharge orifice adjacent the discharge end ofsaid burner resonator, an air inlet connected to said burner, valveforming means connected to the air inlet end of said air resonator tube,a shut-off device with valve and a filter in series in said conduitmeans leading from said medium container to said burner resonator, acontrol'valve in series with said shut off device with valve and filter,a housing member in which said valves and filter are mounted to form aunit, said control valve being biased toward closed position andincluding a movable surface within an expansible pressure chamberresponsive to pressure to urge thereto and including a check valveopening toward the surface, communication means connecting said surfaceto the atmosphere, and lock means for releasably holding said controlvalve in closed position, said control valve including a reciprocablevalve member and said surface being on a diaphragm connected in thecenter to said valve member and on one side forming said movable surfacewithin an expansible pressure chamher, said diaphragm at the peripherybeing sealed to said housing member, said communication means and saidconduit extending through said housing member on said one side of saiddiaphragm, the other side of said diaphragm having substantially freecommunication with the atmosphere.

16. In an apparatus for fuel consumption and ejecting a flowable medium,as for spraying or smoke laying: a container for said medium, apulsating burner having an intake end for admission of a combustiblemixture and a discharge end, and a burner resonator having one endconnected to the burner discharge end and the other end open to form adischarge orifice, conduit means leading from said medium container tosaid burner resonator to supply said medium thereto, an air resonatortube coaxial with and surrounding said burner and burner resonator andhaving an air inlet upstream of the intake end of said burner resonatorand open at the other end to form a discharge orifice adjacent thedischarge end of said burner resonator, an air inlet connected to saidburner, valve forming means connected to the air inlet end of said airresonator tube, said burner including an end section forming a mixingpassage leading substantially at right angles into said one end of saidresonator, the length of said passage bearing a predetermined ratio tothe length of said air resonator tube, said conduit means leading fromsaid medium container to said burner resonator being connected to thelatter near the discharge end thereof, said valve forming means at theair inlet end of said air resonator tube being located upstream fromsaid one end of said burner and comprising a plate having perforationstherein which taper inwardly toward said air resonator tube, andelectrical means for supplying energy to said ignition means, saidelectrical means being disposed between said medium container and saidfuel

1. IN AN APPARATUS FOR FUEL CONSUMPTION AND EJECTING A FLOWABLE MEDIUM,AS FOR SPRAYING OR SMOKE LAYING; A CONTAINER FOR SAID MEDIUM A PULSATINGBURNER HAING AN INTAKE END FOR ADMISSION OF A COMBUSTION MIXTURE AND ADISCHARGE END, AND A BURNER RESONATOR HAVING ONE END CONNECTED TO THEBURNER DISCHARGE END AND THE OTHER END OPEN TO FORM A DISCHARGE ORIFICE,CONDUIT MEANS LEADING FROM SAID MEDIUM CONTAINER TO SAID BURNERRESONATOR TO SUPPLY SAID MEDIUM THERETO, AN AIR RESONATOR TUBE WITH ANDSURROUNDING SAID BURNER AND BURNER RESONATOR AND HAING AN AIR INLETUPSTREAM OF THE INTAKE END OF SAID BURNER RESONATOR AND OPEN AT THEOTHER END TO FORM A DISCHARGE ORIFICE ADJACENT THE DISCHARGE END OF SAIDBURNER RESONATOR AN AIR INLET CONNECTED TO SAID BURNER, VALVE FORINGMEANS CONNECTED TO THE AIR INLET END OF SAID AIR RESONATOR TUBE SAIDBURNER INCLUDING AN END SECTION FORMING A MIXING PASSAGE LEADINGSUBSTANTIALLY AT RIGHT ANGLES INTO SAID ONE END OF SAID RESONATOR THELENGTH OF SAID PASSAGE BEARING A PREDETERMINED RATIO TO THE LENGTH OFSAID AIR RESONATOR TUBE, ASSAID CONDUIT MEANS LEADING FROM SAID MEDIUMCONTAINER TO SAID BURNER RESONATOR BEING CONNECTED TO THE LATTER NEARTHE DISCHAGE END THEREOF, SAID BURNER INCLUDING A CARBUREOR HAVING ATURBULENCE CHAMBER SPACED FROM THE END OF SAID MIXING PASSAGE OPPOSITETHE BURNER END OF THE PASSAGE, A FUEL NOZZLE COAXIAL WITH THE MIXINGPASSAGE AND INTERPOSED BETWEEN THE MIXING PASSAGE AND TURBULENECECHAMBER ANDD SPACED FROM THE ADJACENT END OF THE MIXING PASSAGE, AHELICAL STRIP IN THE END OF SAID END SECTION AND A BAFFLE PLATE AT THEDOWNSTREAM END OF SAID STRIP DEFINING AN ANNULAR SPACE WITH SAID MIXINGPASSAGE SAID AIR INLET COMMUNICATING WITH THE SPACE BETWEEN SAID MIXINGPASSAGE AND SAID NOZZLE AND INGITION MEANS ON THE DOWNSTREAM SICDE OFSAID BAFFLE PLATE FOR IGNITING THE FUEL-AIR MIXTURE IN SAID PASSAGE. 2.An apparatus according to claim 1 in which said valve forming means atthe air inlet end of said air resonator tube is located upstream fromsaid one end of said burner and comprises a plate having perforationstherein which taper inwardly toward said air resonator tube.
 3. Anapparatus according to claim 2 in which said resonator tubes are tunedrelative to each other such that at a natural frequency on the order offrom about 60 to about 150 Hertz the oscillations in said burnerresonator are displaced about a half cycle from the oscillations in saidair resonator tube.
 4. An apparatus according to claim 1 which includesa shut-off device with valve and a filter in series in said conduitmeans leading from said medium container to said burner resonator, acontrol valve in series with said shut-off device with valve and filter,a housing member in which said valve and filter are mounted to form aunit, said control valve being spring biased toward closing position andincluding a movable diaphragm surface within an expansible pressurechamber responsive to pressure to urge the control valve in openingdirection, a conduit leading from said carburetor to said surface tosupply pressure thereto and including a check valve opening toward thesurface, communication means connecting said surface to the atmosphere,and lock means for releasably holding said control valve in closedposition.
 5. An apparatus according to claim 1 which includes a fueltank and a fuel conduit leading therefrom to said nozzle, saidcarburetor and fuel tank forming a unitary structure.
 6. An apparatusaccording to claim 5 which includes a first conduit leading from thespace between the said nozzle and the said passage to said mediumcontainer to supply pressure thereto and having a check valve openingtoward the medium container, a control valve in said conduit meansleading from said medium container and spring-urged toward closedposition and having a movable surface within an expansible pressurechamber responsive to fluid pressure to open the control valve, a secondconduit leading from said space to said expansible chamber and having acheck valve opening toward said expansible chamber, communication meansconnecting to the atmosphere to permit said control valve to close uponinterruption of the supply of pressure from said second conduit to saidexpansible chamber, and fuel flow metering means in said fuel conduit tocontrol the flow of fuel from said tank to said nozzle.
 7. An apparatusaccording to claim 6 which includes a passage-forming means from thespace at the downstream side of said nozzle to said conduit means toassist in the flow of said medium to said burner resonator.
 8. Anapparatus according to claim 6 which includes a passage-forming meansfrom the space at the downstream side of said nozzle to said fuel tankabove the fuel therein.
 9. An apparatus according to claim 6 in whichsaid space at the downstream end of said nozzle is subjected to pressurewhen combustion takes place at the downstream side of said disc and issubjected to subatmospheric pressure between incidents of combustion,and said air inlet is disposed between the atmosphere and said space andis in the form of an opening toward said space.
 10. An apparatusaccording to claim 6 in which said fuel flow metering means comprises ahousing part having a tubular channel connecting said fuel conduit tosaid nozzle, a filter at the upstream end of said channel, a bushing inthe channel at the downstream end of said filter having a central bore,a plug adjustable in said bushing for opening and closing the downstreamend of said bore, and a needle valve adjustable in said plug foradjustably controlling the flow of fuel through said bore.
 11. Anapparatus according to claim 10 in which said filter and bushing andplug and needle valve are in the form of a unitary structure insertablein and removable from said channel as a unit, said housing partincluding a separable portion defining at least a part of said secondconduit and a part of said channel, said bushing having an end flangeoverlying said separable portion and being threaded into said housingpart thereby to clamp said portion to said housing, said portion havingtherein the said check valve in said second conduit and a filter elementserially connected to the check valve.
 12. An apparatus according toclaim 10 in which said plug is threaded into said bushing and has oneend protruding from the bushing, a handle removeably mounted on theprotruding end of said plug, and means on the bushing to limit therotation of said handle when mounted on the plug.
 13. An apparatusaccording to claim 10 which includes a manually operable air pump, and aconduit connecting the discharge side of said air pump to saidturbulence chamber and including a check valve opening toward saidturbulence chamber.
 14. In an apparatus for fuel consumption andejecting a flowable medium, as for spraying or smoke laying: a containerfor said medium, a pulsating burner having an intake end for admissionof a combustible mixture and a discharge end, and a burner resonatorhaving one end connected to the burner discharge end and the other endopen to form a discharge orifice, conduit means leading from said mediumcontainer to said burner and burner resonator to supply said mediumthereto, an air resonator tube coaxial with and surrounding said burnerresonator and having an air inlet upstream of the intake end of saidburner resonator and open at the other end to form a discharge orificeadjacent the discharge end of said burner resonator, an air inletconnected to said burner, valve forming means connected to the air inletend of said air resonator tube, a shut off device with valve and afilter in series in said conduit means leading from said mediumcontainer to said burner resonator, a control valve in series with saidshut off device with valve and filter, a housing member in which saidvalve and filter are mounted to form a unit, said control valve beingspring biased toward closed position and including a movable diaphragmsurface within an expansible pressure chamber responsive to pressure tourge the control valve in opening direction, a conduit leading from saidcarburetor to said surface to supply pressure thereto and including acheck valve opening toward the surface, communication means connectingsaid surface to the atmosphere, and lock means for releasably holdingsaid control valve in closed position, said housing member being formedof two parts in face-to-face sealed engagement and defining therebetweenthe portions of said conduit means leading between said valve andfilter.
 15. In an apparatus for fuel consumption and ejecting a flowablemediUm, as for spraying or smoke laying: a container for said medium, apulsating burner having an intake end for admission of a combustiblemixture and a discharge end, and a burner resonator having one endconnected to the burner discharge end and the other end open to form adischarge orifice, conduit means leading from said medium container tosaid burner resonator to supply said medium thereto, an air resonatortube coaxial with and surrounding said burner and burner resonator andhaving an air inlet upstream of the intake end of said burner resonatorand open at the other end to form a discharge orifice adjacent thedischarge end of said burner resonator, an air inlet connected to saidburner, valve forming means connected to the air inlet end of said airresonator tube, a shut-off device with valve and a filter in series insaid conduit means leading from said medium container to said burnerresonator, a control valve in series with said shut off device withvalve and filter, a housing member in which said valves and filter aremounted to form a unit, said control valve being biased toward closedposition and including a movable surface within an expansible pressurechamber responsive to pressure to urge the control valve in openingdirection, a conduit leading from said burner to said surface to supplypressure thereto and including a check valve opening toward the surface,communication means connecting said surface to the atmosphere, and lockmeans for releasably holding said control valve in closed position, saidcontrol valve including a reciprocable valve member and said surfacebeing on a diaphragm connected in the center to said valve member and onone side forming said movable surface within an expansible pressurechamber, said diaphragm at the periphery being sealed to said housingmember, said communication means and said conduit extending through saidhousing member on said one side of said diaphragm, the other side ofsaid diaphragm having substantially free communication with theatmosphere.
 16. In an apparatus for fuel consumption and ejecting aflowable medium, as for spraying or smoke laying: a container for saidmedium, a pulsating burner having an intake end for admission of acombustible mixture and a discharge end, and a burner resonator havingone end connected to the burner discharge end and the other end open toform a discharge orifice, conduit means leading from said mediumcontainer to said burner resonator to supply said medium thereto, an airresonator tube coaxial with and surrounding said burner and burnerresonator and having an air inlet upstream of the intake end of saidburner resonator and open at the other end to form a discharge orificeadjacent the discharge end of said burner resonator, an air inletconnected to said burner, valve forming means connected to the air inletend of said air resonator tube, said burner including an end sectionforming a mixing passage leading substantially at right angles into saidone end of said resonator, the length of said passage bearing apredetermined ratio to the length of said air resonator tube, saidconduit means leading from said medium container to said burnerresonator being connected to the latter near the discharge end thereof,said valve forming means at the air inlet end of said air resonator tubebeing located upstream from said one end of said burner and comprising aplate having perforations therein which taper inwardly toward said airresonator tube, and electrical means for supplying energy to saidignition means, said electrical means being disposed between said mediumcontainer and said fuel tank.